Are soy or tofu products really bad for you?

The effects of phytoestrogens hotly debated. Some studies have showen a slight decrease in male fertility in men who ate large amounts of phytoestrogens in childhood. Many people think phytoestrogens have a beneficial effect on older women. The theory is that phytoestrogens are much weaker than women’s own estrogens so before menopause it reduces the effect of women’s own estrogens then after menopause it supplies a weak hormone to replace women’s missing estrogen. If it makes the hormonal change less abrupt it may reduce the symptoms of menopause. Some studies have shown a reduction of breast and ovarian cancers in women who eat soy; since both of these cancers are related to estrogen the effect of phytoestrogen blocking estrogen may explain this effect. Of course some other studies show no benefit so this is all up in the air as well.

I think the popular magazine articles and books calling soy products poisen are junk science but I do believe that when it comes to food it is best to eat a variety of foods and less processed the food is the better. I think the best way to eat soy is probably edamame; I also find edamame quite tasty. I also don’t worry a lot about tofu, soy sauce, and miso since I don’t eat these in large quantities. I do think that soy burgers, sausage, etc. are too processed and being made from soy protein isolate expose you to more phytoestrogens than you would get from less processed and less concentrated forms of soy. I will have an occasional veggie burger when we are grilling but I avoid them as daily fare.

As long as you eat a variety of good foods you will get plenty of protein; there is really nothing to worry about here.